Talk:Long multiplication

BigNum

Wouldn't it be appropriate to replace this task with arbitrary-precision arithmetic implementation? I.e. long to long +, -, *, /, and long to short +, -, *, /. The divisions are to be implemented in a complete form (result + remainder).

Hi User_talk:Dmitry-kazakov. Yes that makes sense. For the moment I'll switch this task to be a member of Category:Arbitrary precision. IIRC the Newton Raphson Kontorovich method can be used to speed up the division. It looks interesting....

Re: long/short implementations... I spotted the Ada Rational Arithmetic sample code with "long + short" and considered replicating. But by the time if counted all the combinations I ran out of fingers and toes. E.g. one would have to combine the short..., short short, short, long, long long, long... for int, real, compl for the operators "+", "-", "/", "*", "%", "%*", "**", etc ... ALSO: ×, ÷, ... abs, over, mod up, bin etc ... together with "+:=", "-:=" etc ...

Result: No more toes... I think C++/Ada templates can manage this kind of complexity.

The ALGOL 68 standard had a shorthand/template ≮L≯ for this. e.g.

op ≮÷*, %*, ÷×, %×, mod≯  = (L int a, i) L int: ...

But this for the compiler writer, and not available to programmers.

NevilleDNZ 10:56, 26 February 2009 (UTC)